This invention generally relates to a bicycle shift notification apparatus. More specifically, the present invention relates to a bicycle shift notification apparatus for producing a notification based on a determination of the current operating state of a bicycle transmission, which has a plurality of speed stages.
Currently, most bicycle transmissions are manually operated by a shift operating wire connected between a manual transmission and a manually operated shift operating device mounted on the handlebar. The rider operates the shift operating device to selectively pull or release the shift operating wire which, in turn, operates a derailleur of the transmission in the desired manner. More recently, bicycles have been provided with an electric drive train for smoother and easier shifting. Electric drive trains may be operated manually or automatically. In manually operated electric drive trains, usually, a button or lever on a shift control device mounted to the bicycle handlebar is manipulated so that a gear shift command is output to operate a motor for upshifting or downshifting the bicycle transmission. In automatically operated electric drive trains, the gear shift commands are generated automatically based on various running conditions of the bicycle.
In some manual and automatic bicycle transmissions, a notification device such as a display is provided to show current gear positions. Also some bicycle transmission control systems include a sound-producing device such as a buzzer or the like for producing a sound each time the transmission is operated to change a gear position of the transmission. For example, in the case of an automatic transmission, a sound can be produced after operating the motor to change a gear position of the transmission. As a result, the rider is informed of the shifting operation only while the actual shifting operation is being conducted. Another example of a shift notification apparatus is disclosed in U.S. Pat. No. 6,774,771 (assigned to Shimano Inc.). In this patent, every time a gear shifting operation occurs, the apparatus informs a rider of an upcoming shifting operation in a bicycle transmission based on a running condition of the bicycle.